package containers;//: containers/TypesForSets.java
// Methods necessary to put your own type in a Set.

import java.util.*;

//唯一元素实现equals  无重复
class SetType {
    int i;

    public SetType(int n) {
        i = n;
    }

    public boolean equals(Object o) {
        return o instanceof SetType && (i == ((SetType) o).i);
    }

    public String toString() {
        return Integer.toString(i);
    }
}

// hashCode
class HashType extends SetType {
    public HashType(int n) {
        super(n);
    }

    public int hashCode() {
        return i;
    }
}

//拍讯
class TreeType extends SetType implements Comparable<TreeType> {

    public TreeType(int n) {
        super(n);
    }

    public int compareTo(TreeType arg) {
        return (arg.i < i ? -1 : (arg.i == i ? 0 : 1));
    }
}

public class TypesForSets {
    //测试方法
    static <T> Set<T> fill(Set<T> set, Class<T> type) {
        try {
            for (int i = 0; i < 10; i++) {

                set.add(type.getConstructor(int.class).newInstance(i));
            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        return set;
    }

    static <T> void test(Set<T> set, Class<T> type) {
        fill(set, type);
        fill(set, type); // Try to add duplicates  重复填充容器，看Set是否重复
        fill(set, type);
        System.out.println(set);
    }

    public static void main(String[] args) {
        // 无序，但是无重复
        test(new HashSet<HashType>(), HashType.class);
        // 插入顺序，不重复
        test(new LinkedHashSet<HashType>(), HashType.class);
        // 有序，不重复
        test(new TreeSet<TreeType>(), TreeType.class);
        // Things that don't work:   重复  HashSet
        test(new HashSet<SetType>(), SetType.class);
        test(new HashSet<TreeType>(), TreeType.class);
        //LinkedHashSet
        test(new LinkedHashSet<SetType>(), SetType.class);
        test(new LinkedHashSet<TreeType>(), TreeType.class);
        // TreeSet
        try {
            test(new TreeSet<SetType>(), SetType.class);
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
        try {
            test(new TreeSet<HashType>(), HashType.class);
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
    }
} /* Output: (Sample)
[2, 4, 9, 8, 6, 1, 3, 7, 5, 0]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
[9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
[9, 9, 7, 5, 1, 2, 6, 3, 0, 7, 2, 4, 4, 7, 9, 1, 3, 6, 2, 4, 3, 0, 5, 0, 8, 8, 8, 6, 5, 1]
[0, 5, 5, 6, 5, 0, 3, 1, 9, 8, 4, 2, 3, 9, 7, 3, 4, 4, 0, 7, 1, 9, 6, 2, 1, 8, 2, 8, 6, 7]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
java.lang.ClassCastException: SetType cannot be cast to java.lang.Comparable
java.lang.ClassCastException: HashType cannot be cast to java.lang.Comparable
*///:~
